


Polaris

by GM_3826 (orphan_account)



Category: Under Night In-Birth (Video Game)
Genre: Alternate Universe - Canon Divergence, Canon-Typical Violence, Developing Relationship, Gen, Other Additional Tags to Be Added, Spoilers
Language: English
Status: In-Progress
Published: 2020-02-24
Updated: 2020-02-26
Packaged: 2021-02-27 22:34:29
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 2
Words: 1,065
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22883368
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/GM_3826
Summary: Byakuya is defeated by Hyde, and the latter is forced to kill him. Regretting his mistake, Hyde offers to help Byakuya's sister find her lost friend.
Kudos: 1





	1. Chapter 1

The battle was over quickly.

Hyde wasn't a particularly skilled fighter. He had a month of combat training and a few years of kendo practice under his belt, but that was nothing compared to the breadth of experience of many other Wielders. That said, Byakuya had absolutely no training and very little experience. He had just come into his EXS, and while he would have an advantage in terms of raw power against many other Wielders, Hyde was not as weak as Byakuya thought.

It's possible that if things had gone even slightly differently, Byakuya would have won. Instead, Byakuya was within an inch of his life. Hyde had the advantage, with his sword the Insulator pointed directly at Byakuya's Vessel.

"Wait." Byakuya's eyes widened. "We can still negotiate. I wasn't really planning on eating you, OK? Please don't kill me..."

"What the hell? You never said anything about eating me." Hyde looked at the spiderlike arms jutting out of Byakuya's back. "What in the world are you?"

"...No, no, no. I can't let you hurt my sister..." Byakuya foamed at the mouth.

"I wasn't planning on hurting her in the first place!" Hyde shouted. "None of this would have happened if you didn't choose to pick a fight with me. You said you wanted to talk this out!"

"W-we can still do that!" Byakuya begged.

"Then I have a lot of questions for you." Hyde said. "First off, why the hell are you so overprotective?"

"My sister's Vessel broke, so I need to protect her." Byakuya replied.

_OK, her Vessel broke. That explains why I'm not sensing any EXS from her_. Hyde thought _. But that still doesn't answer my question..._

At that point, he realized something.

"Why are both you and your sister an In-birth? The chances of that seem astronomically low." Hyde didn't know much about the Hollow Night, but at the very least, he was able to piece together that EXS didn't run in families. If there were any exceptions, he wasn't aware of them.

"...Why are you asking so many questions about my sister? Are you planning on taking her away?" Byakuya's voice cracked.

"What? No! Why would you ask that?" Hyde shouted. "Again, you just said you were willing to talk this out!"

"Oh, what the hell. Sis' doesn't want me anyways..." Byakuya cried. "You'll just take her away, and then I'll never see her again. I can't let that happen..."

At that point, his back opened up to reveal a mouth wide enough to swallow a man whole. It was much larger on the inside than his small size suggested. His spiderlike arms reached out to grab Tsukuyomi, but Hyde's hand reacted faster than he did. Byakuya's heart had been pierced before Hyde fully comprehended what was going on. As Byakuya felt the Insulator tear through his flesh, he let out a bloodcurdling scream. After that, he evaporated into mist, just like the monsters that crawled through the Night.

Hyde looked at the sword in his hand, now stained red with blood, before looking Tsukuyomi in the eyes.

"...I'm sorry. Your brother was a jerk, but I wasn't planning on killing him." He said.

"...Don't worry. It's not your fault. Honestly, I have some questions to ask you, as well." Tsukuyomi replied.

"...You sure about that? I know I don't look like the most trustworthy person." Hyde seemed surprised by just how frank Tsukuyomi was.

She sighed. "I don't have much choice. Where are you heading?"

"To the Altar of Heaven and Darkness." Hyde replied. "Why do you ask?"

"...Would you be willing to accompany me?" Tsukuyomi asked. "I'm here to find a friend of mine, and my brother wasn't lying when he said my Vessel broke."

Hyde took a moment to think about it. Finally, he responded.

"...If I'm the one who killed your brother. I'm the one who should face the consequences."

"...In that case, we have a lot to talk about."


	2. Chapter 2

When Hyde and Tsukuyomi first started traveling together, things were very quiet. There was a sort of stillness in the air, as they could not stop thinking about Byakuya. While he would not be mourned. Byakuya's death ate at Hyde's conscience, and although Tsukuyomi used Byakuya as a tool, she was still grateful for his help. After about 15 minutes, Hyde chooses to break the silence, if only to clear things up.

"Alright, first thing's first. What's your name?"

"Hmm." Tsukuyomi raises an eyebrow. "Up until now, I've gone by the name of Tsukuyomi, but I need to change that."

"Why? Is that your real name?" Hyde asks. He understood that it was unusual that he used his real name as an In:birth. Although he could not and would not lie about who he was, he got why others might want to protect their identity.

"Quite the opposite. That was Byakuya's sister's name, and I wasn't actually his sister." Tsukuyomi says.

"What? Then why was Byakuya so affectionate towards you?" Hyde raises his voice slightly.

"He said that I reminded him of his sister, but his sister died before I even met him. I guess he saw me as a replacement." Tsukuyomi strokes her hair idly.

"That bastard..." Hyde sputtered. "In that case, what should I call you?"

Tsukuyomi thought about it for a moment before she replied. "Call me Polaris." She said.

"Alright, Polaris. Got it." Hyde lowered his voice. "You can call me Hyde. One last question. Who is your friend? What happened to her?"

Polaris was quiet for a moment before she began to speak. "She was someone who I worked with when I was an In:birth. Someone we looked up to died and she overreacted. She was jealous and thought that I spent too much time with him, so she took out her anger on me. The last I saw of her was a monstrous look in her eyes before she shattered my Vessel and I collapsed." She sighs. "I wish I could have done something to prevent it, but seeing my friend right then and there... I was powerless."

Polaris gave off a half-hearted smile. "As a side note, that was two questions."

"...Nevermind that. I can't imagine what that was like." Hyde said. "It's not like I _understand_ , but I'll do everything I can to help you find her."

Polaris' eyes dilate ever so slightly. "...Thank you."

**Notes for the Chapter:**

> This chapter is a quick breather before we get back into the story. The only plot-important piece of information is Tsukuyomi's new codename, which is the title of this fanfiction. Original, I know. Beyond that, this really could have been handled off-screen, with it being assumed Tsukuyomi told Hyde everything, but this tells us exactly what Hyde knows.

**Author's Note:**

> This is going to be a relatively short fanfiction. I just looked at what I had written so far and thought "this is going to be at _least_ two chapters." It's possible that after a sequel is released I might expand on this and reveal how the events of that game change with Byakuya's death, but that's almost certainly going to be in the form of a sequel to this story, and I can't promise you that.
> 
> Basic concept behind this is "what happens when Byakuya gets a Game Over in stage 3 of his Arcade mode scenario?" Canonically, there's no answer. Conceptually, I thought this was an interesting idea. We know that Hyde is willing to help out just about anyone, so his answer would almost certainly be "help escort Tsukuyomi," and Tsukuyomi would be willing to accept this because Byakuya has no real loyalty to her at that point and she's not particularly attached to him. That's not something we're ever going to see, though. I doubt any characters are going to be dead by next game, and Byakuya's scenario presumably isn't canon anyways. So think of this as a "what-if." It might seem like a fix-it, but that wasn't what I was going for. This situation will present some conflict.
> 
> One more question you might have is "will this become romantic?" The answer is that I haven't decided yet. As a result, the tags could change. In that regard, I'm just going to roll with whatever feels right, although I doubt Hyde is going to return Tsukuyomi's feelings by the end of the story.
> 
> If you have any critiques, I'm curious about whether or not each character's _dialogue_ sounds in-character, although whether or not their actions are is not something I'm worried about.


End file.
